Highland GuanPenelopina nigra

Demography and Populations

Population density estimates range from 1-7 birds/km2 at Montaña Caquipec, Alta Verapaz (Eisermann 1999), 9-10 birds/km2 at Montaña Yalijux, Alta Verapaz (Renner 2003), 6-27 birds/km2 in Sierra de las Minas (Morales 2004), and 6-106 birds/km2 in Quetzaltenango (Morales 1991). Estimates higher than 25 birds/km2 likely are erroneous due to sampling error (Eisermann et al. 2006). Based on an area of occupancy of 15,200 km2 and an assumed average density of 6 birds/km2, world population of Highland Guan has been estimated to be 91,200 birds (Eisermann et al. 2006). Overall population is declining because of ongoing reduction of suitable habitat due to human activity (Eisermann et al. 2006). Continuous monitoring of abundance in cloud forest at Montaña Sacranix, Alta Verapaz from 2004–2012 indicated a negative, but statistically not significant, trend (K. Eisermann, unpublished). Highland Guans become sexually mature at two years of age (González-García et al. 2001). Life span, survivorship, diseases, parasites on wild birds, and dispersal remain unknown.